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871.
N. H. Ravindranath Rajiv K. Chaturvedi N. V. Joshi R. Sukumar Jayant Sathaye 《Mitigation and Adaptation Strategies for Global Change》2011,16(2):211-227
Climate change is projected to impact forest ecosystems, including biodiversity and Net Primary Productivity (NPP). National
level carbon forest sector mitigation potential estimates are available for India; however impacts of projected climate change
are not included in the mitigation potential estimates. Change in NPP (in gC/m2/yr) is taken to represent the impacts of climate change. Long term impacts of climate change (2085) on the NPP of Indian
forests are available; however no such regional estimates are available for short and medium terms. The present study based
on GCM climatology scenarios projects the short, medium and long term impacts of climate change on forest ecosystems especially
on NPP using BIOME4 vegetation model. We estimate that under A2 scenario by the year 2030 the NPP changes by (−5) to 40% across
different agro-ecological zones (AEZ). By 2050 it increases by 15% to 59% and by 2070 it increases by 34 to 84%. However,
under B2 scenario it increases only by 3 to 25%, 3.5 to 34% and (−2.5) to 38% respectively, in the same time periods. The
cumulative mitigation potential is estimated to increase by up to 21% (by nearly 1 GtC) under A2 scenario between the years
2008 and 2108, whereas, under B2 the mitigation potential increases only by 14% (646 MtC). However, cumulative mitigation
potential estimates obtained from IBIS—a dynamic global vegetation model suggest much smaller gains, where mitigation potential
increases by only 6% and 5% during the period 2008 to 2108. 相似文献
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875.
Cena LG Keren N Li W Carriquiry AL Pawlovich MD Freeman SA 《Journal of Safety Research》2011,42(4):241-252
Introduction
A common contention is that the construction of highway bypasses negatively impacts the economy of local communities by reducing pass-by traffic for businesses. However, as access to specific business' account records is limited, this impact is difficult to quantify. Another common contention is that bypasses contribute to a reduction in overall crashes in the community and in the surrounding areas. Even though a large number of bypasses have been constructed in the State of Iowa over the past several years, their actual impact in terms of traffic safety has not been quantified.Objectives
This study seeks answers to the following questions: (a) Are bypasses in Iowa associated with a reduction in crash frequencies and crash rates on the bypassed highway? (b) Do bypasses in Iowa introduce a reduction of overall crash frequencies and rates or do they merely shift crashes from the highways through the communities to the bypasses with no significant overall reduction?Method
We obtained crash information from the Iowa DOT at 19 sites on which a bypass was constructed sometime during the past 23 years. We also obtained the same information at six sites used as comparison sites on which no bypasses were constructed at least until 2005. We them employed a Bayesian approach to estimating the association between the construction of the bypass and crash rates, while also accounting for other factors.Results
The construction of bypasses in Iowa is associated with a significant increase in traffic safety both on the main road through town and on the combined main road and bypass roadway. 相似文献876.
Robin M. Pitblado John L. Woodward 《Journal of Loss Prevention in the Process Industries》2011,24(6):827-836
The authors have recently undertaken a major review of LNG consequence modeling, compiling a wide range of historical information with more recent experiments and modeling approaches in a book entitled “LNG Risk-Based Safety: Modeling and Consequence Analysis”. All the main consequence routes were reviewed – discharge, evaporation, pool and jet fire, vapor cloud explosions, rollover, and Rapid Phase Transitions (RPT’s). In the book, experimental data bases are assembled for tests on pool spread and evaporation, burn rates, dispersion, fire and radiation and effects on personnel and structures. The current paper presents selected highlights of interest: lessons learned from historical development and experience, comparison of predictions by various models, varying mechanisms for LNG spread of water, a modeling protocol to enable acceptance of newer models, and unresolved technical issues such as cascading failures, fire engulfment of a carrier, the circumstances for a possible LNG BLEVE, and accelerated evaporation by LNG penetration into water. 相似文献
877.
硫酸铜和氰戊菊酯对斑马鱼急性毒性试验 总被引:1,自引:1,他引:1
为探究重金属和农药对斑马鱼的毒性与安全评价,选用硫酸铜、氰戊菊酯对斑马鱼进行急性毒性试验,以24~96h半致死浓度(LC50)判定斑马鱼对这两种药物的敏感性.结果表明,硫酸铜24 hLC50、48h LC50、72 h LC50、96h LC50分别为12mg/L、7.9 mg/L、6.8mg/L、5.4 mg/L;氰戊菊酯24 h LC50、48h LC50、72h LC50、96h LC50分别为1.2×10-4 mg/L、0.9×10-4 mg/L、0.9×10-4 mg/L、0.9×10-4 mg/L; 硫酸铜安全质量浓度为1.03mg/L,氰戊菊酯为1.52×1O-5 mg/L.参照我国化学物质对鱼类毒性分级标准,判定硫酸铜对斑马鱼急性毒性为Ⅱ级,氰戊菊酯对斑马鱼急性毒性为Ⅰ级. 相似文献
878.
Rubenstein LZ Vivrette R Harker JO Stevens JA Kramer BJ 《Journal of Safety Research》2011,42(6):493-499
Background
Falls are a common, serious, and often unrecognized problem facing older adults. The objective of this study was to provide an initial clinical and statistical validation for a public health strategy of fall risk self-assessment by older adults using a Fall Risk Questionnaire (FRQ).Methods
Adults age 65 + (n = 40) were recruited at a Los Angeles Veterans Affairs (VA) medical facility and at a local assisted living facility. Participants completed the FRQ self-assessment and results were compared to a “gold standard” of a clinical evaluation of risks using the American/British Geriatrics Society guidelines to assess independent predictors of falls: history of previous falls, fear of falling, gait/balance, muscle weakness, incontinence, sensation and proprioception, depression, vision, and medications. For the comparison, we used an iterative statistical approach, weighing items based on relative risk.Results
There was strong agreement between the FRQ and clinical evaluation (kappa = .875, p < .0001). Individual item kappa values ranged from .305-.832. After dropping one FRQ item (vision risk) because of inadequate agreement with the clinical evaluation (kappa = .139, p = .321), the final FRQ had good concurrent validity.Conclusions
The FRQ goes beyond existing screening tools in that it is based on both evidence and clinical acceptability and has been initially validated with clinical examination data. A larger validation with longitudinal follow-up should determine the actual strength of the FRQ in predicting future falls. 相似文献879.
880.